Collapsible medical device having an open lumen

ABSTRACT

The present disclosure provides collapsible medical devices that are formed from a braided tubular member configured to allow the braided tubular member to be terminated into one or more marker bands while maintaining an open lumen from a proximal end to a distal end. The collapsible medical device including the braided tubular member can be easily pulled down into a delivery sheath or other delivery device so that it is suitable for use with a number of delivery devices. The marker bands, which provide one or more attachment points for a medical device/delivery system, are positioned at one or more locations on the braid such that the braid is fixed and cannot unravel, thus preventing entanglement between individual braid wires and malformation of the device.

CROSS REFERENCE OF RELATED APPLICATION

This application claims priority to U.S. Provisional Application Ser.No. 62/500,737, filed May 3, 2017 which is incorporated by reference inits entirety.

BACKGROUND OF THE DISCLOSURE Field of the Disclosure

The present disclosure generally relates to a collapsible medical deviceand methods of making and using the same. In particular, the presentdisclosure relates to a collapsible medical device formed from a braidedtubular member that has an open lumen from a proximal end to a distalend. The collapsible medical device may be collapsed into a deliverydevice for delivery or attached to another medical device. Methods ofmanufacturing and using the collapsible medical devices including theopen lumen are also disclosed.

Background Art

A wide variety of intravascular medical devices are used in variousmedical procedures within the body. Certain intravascular medicaldevices, such as catheters and guidewires, are generally used simply todeliver fluids or other medical devices to specific locations within apatient's body, such as a selective site within the vascular system.Other, frequently more complex, collapsible intravascular devices areused in treating specific conditions, such as devices used in removingvascular occlusions, for treating septal defects, for valvereplacements, stent introduction, and the like. Many of these morecomplex collapsible intravascular devices are constructed, at least inpart, of a braided tubular member, such as a nitinol braided tubularmember.

In many cases where it is desirable to utilize an intravascular cardiaccollapsible medical device, it may be advantageous to provide acollapsible medical device formed from a braided tubular member thatincludes an open lumen from a proximal end to a distal end to allow forthe passage of fluids and/or for the introduction of a separate medicaldevice therethrough. Such a collapsible medical device may beparticularly advantageous for thoracic grafts, embolic protectiondevices, and atrial seals for transcatheter mitral valves, for example.

SUMMARY OF THE DISCLOSURE

The present disclosure is directed to a collapsible medical device. Thecollapsible medical device comprises: (i) a tubular member formed of aplurality of wires and having a preset, expanded configuration and acollapsed configuration, the tubular member having a center portionwherein the wires are in a braided configuration, and a distal end and aproximal end wherein the wires are in an unraveled configuration; (ii)an open lumen extending from the proximal end to the distal endconfigured to allow passage of a fluid therethrough in the preset,expanded configuration; (iii) at least one securement mechanism coupledto the proximal end; and (iv) at least one securement mechanism coupledto the distal end. Each securement mechanism is configured to secure atleast a portion of the plurality of wires in the unraveled configurationnear an outer circumference of the open lumen.

The present disclosure is further directed to a collapsible medicaldevice. The collapsible medical device comprises: (i) an invertedbraided tubular member comprising a first set of wire endslongitudinally aligned with a second set of wire ends at a distal endthereof, and an open lumen extending between the distal end and aproximal end of the inverted braided tubular member; and (ii) at leastone securement mechanism positioned near an outer circumference of theinverted braided tubular member on the distal end thereof.

The present disclosure is further directed to a method of forming acollapsible medical device having an open lumen. The method comprises:(i) coupling at least one braid marker to a tubular member comprising aplurality of braided wires, the tubular member having a distal end and aproximal end; (ii) unraveling the braided member along a longitudinalline extending from the at least one braid marker to the proximal end orthe distal end to form one or more sections of unraveled wires; (iii)coupling a securement mechanism to each section of unraveled wires; and(iv) securing each securement mechanism to the respective section ofunraveled wires.

The present disclosure is further directed to a method of forming acollapsible medical device having an open lumen. The method comprises:(i) inverting a proximal end of a braided tubular member over itselftoward a distal end of the braided tubular member to form an inner layerand an outer layer; (ii) longitudinally aligning wire ends of theproximal end and the distal end of the braided tubular member; (iii)coupling at least one braid marker to the inner and outer layer of thebraided tubular member; (iv) unraveling the inner layer and the outerlayer along a longitudinal line extending from each braid marker to thewire ends to form a section of unraveled wires between each respectivebraid marker; (v) coupling a securement mechanism to each section ofunraveled wires; and (vi) securing each securement mechanism to therespective section of unraveled wires.

The foregoing and other aspects, features, details, utilities, andadvantages of the present disclosure will be apparent from reading thefollowing description and claims, and from reviewing the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a braided tubular member suitable forthe forming of a collapsible medical device of the present disclosure;

FIG. 2 is the braided tubular member of FIG. 1 illustrating unraveledportions thereof during formation of the collapsible medical device;

FIG. 3 is the braided tubular member of FIG. 2 illustrating theplacement of various marker bands near the distal end of the braidedtubular member;

FIG. 4 is the braided tubular member of FIG. 3 further illustrating theproximal end of the braided tubular member;

FIG. 5 is the braided tubular member of FIG. 4 after it has beenheat-treated into a desired pre-set configuration;

FIGS. 6A and 6B are flow diagrams of a method of forming a collapsiblemedical device including an open lumen;

FIG. 7 is a perspective view of a collapsible medical device includingan open lumen in accordance with one embodiment of the presentdisclosure;

FIG. 8 is a perspective view of a collapsible medical device includingan open lumen in accordance with another embodiment of the presentdisclosure;

FIGS. 9A and 9B are flow diagrams of a method of forming a collapsiblemedical device including an open lumen;

FIG. 10 is a side view of a collapsible medical device of the presentdisclosure used in combination with a mitral valve;

FIG. 11 is a top view of the collapsible medical device of the presentdisclosure and mitral valve of FIG. 10.

DETAILED DESCRIPTION OF THE DISCLOSURE

The fabrication of collapsible medical devices constructed of a braidedtubular member that include an open lumen from the distal end to theproximal end has, to date, been difficult. Some of the previous methodsused to form a desired open lumen extending from the distal end to theproximal end of the collapsible medical device have included the use ofa forming tool that is forced through a pick of the braided material toopen up and spread the braid apart. This method, however, has been metwith generally ineffective results since the forming tool size has beenlimited by the amount of braid that could be stretched around the tool.Other methodologies employed have not produced the desired results. Assuch, it would be desirable to provide a collapsible medical deviceincluding an open lumen from a proximal end to a distal end that couldeasily be collapsed and introduced into a delivery sheath or otherdelivery device, or easily attached to another medical device.

The present disclosure is directed to a collapsible medical device thatincludes a braided tubular member, such as a nitinol braided tubularmember, where the braided pattern is configured to allow wire ends ofthe braided tubular member to be terminated into one or moresecurement/attachment points while maintaining a complete open lumenthrough the collapsible medical device. Along with providing atermination point, the securement/attachment points may also act as apoint for the attachment of another medical device and/or a medicaldelivery device. After formation, the collapsible medical devices of thepresent disclosure including the open lumen may be further heat treatedto a desired pre-set conformation. In many embodiments, the collapsiblemedical device including the braided tubular member is constructed suchthat can be easily pulled down into a delivery sheath or other deliverydevice so that it is suitable for use with a number of medical anddelivery devices.

The securement/attachment points, which, as noted above, may provide oneor more attachment points for attachment to another medical device, suchas a stent, or attachment to a delivery system, offer additionaladvantages as well. These securement/attachment points are positioned onthe braid such that the braid is fixed and cannot unravel, thuspreventing entanglement between individual braid wires and unwantedmalformation of the braided device. Additionally, free wire (or strand)ends are eliminated, thus reducing any potential unwanted contact offree wire ends with other materials or tissue in the body. The number ofsecurement/attachment points utilized in the forming of the collapsiblemedical devices of the present disclosure is a design choice as furtherdiscussed herein, as the larger the number of securement/attachmentpoints used the shorter the securement/attachment sections become. Insome embodiments described herein, the collapsible medical deviceincludes one or more securement/attachment points at both a distal endand a proximal end of the collapsible medical device. In otherembodiments described herein, the braided tubular member is invertedover itself during the forming process such that one or moresecurement/attachment points are located only at a single end of thecollapsible medical device.

The collapsible medical devices of the present disclosure are formedfrom a braided tubular member that comprises a plurality of wires. Inmany embodiments, the wires are all of generally the same length; thatis, the wires that comprise the braided tubular member are allsubstantially the same length or exactly the same length. In otherembodiments, the wires forming the plurality of wires may be ofdifferent lengths. In some embodiments, by having the wires ofsubstantially or exactly the same length throughout the collapsiblemedical device, the braided tubular member may be easily pulled downinto a catheter or other delivery device after formation as describedherein. The braided tubular member may be fabricated with any number ofwires that terminate into one or more securement/attachment points, asfurther described herein. In many embodiments described herein, it isnot required that an equal number of wires be divided among thesecurement/attachment points; that is, when more than onesecurement/attachment point is utilized on the braided tubular member,each securement/attachment point may or may not include the same numberof wires, as further described below.

The braided tubular members used to form the collapsible medical devicesof the present disclosure are generally constructed of a plurality ofwires or strands generally provided as a tubular metal fabric. Thetubular metal fabric is formed of woven metal wires or strands that areheat set after formation into the desired configuration as more fullydescribed below. The woven metal wires are a plurality of conventionalwires that have a predetermined relative orientation between the wires.The wires define two sets of essentially parallel generally helicalstands, with the strands of one set having a “hand”, i.e., a directionof rotation, opposite that of the other set. These helical wires definea generally tubular metal fabric, known in the metal fabric industry asa tubular braid.

The pitch of the wires (i.e., the angle defined between the turns of thewire and the axis of the braid) and the pick of the fabric (i.e., thenumber of wire crossovers per unit length) may be adjusted as known bythose of skill in the art based on the disclosure herein toincrease/decrease/optimize the rigidity/strength as desired for aparticular application. The wires of the metal fabric used to constructthe collapsible medical devices described herein are desirably formed ofa material that is both resilient and that can be heat treated tosubstantially set a desired shape. Materials that are suitable for thispurpose include a cobalt-based low thermal expansion alloy referred toin the field as Elgeloy, nickel-based high temperature high-strengthsuperalloys commercially available from Haynes International under thetrade name Hastelloy, nickel-based heat treatable alloys sold under thename Incoloy by International Nickel, and a number of different gradesof stainless steel. An important factor in choosing a suitable materialfor the wires is that the wires retain a suitable amount of thedeformation induced by a molding process when subjected to apredetermined heat treatment.

One class of materials that are desirable is memory-shape alloys. Suchalloys tend to have a temperature induced phase change that will causethe material to have a preferred configuration that can be fixed byheating the material above a certain transition temperature to induce achange in the phase of the material. When the alloy is cooled back down,the alloy will “recall” the shape it was in during the heat treatmentand will tend to assume that configuration unless constrained from doingso.

One particularly desirable memory shape alloy for use in the presentdisclosure is nitinol, an approximately stoichiometric alloy of nickeland titanium, which may also include minor amounts of other metals toachieve desired properties. Nickel-titanium alloys are very elastic andare commonly referred to as “superelastic” or “pseudoelastic.” Theelasticity of these alloys helps a medical device return to an expandedconfiguration for deployment inside of the body following passage in adistorted or collapsed form through a delivery catheter. Nitinol is aparticularly desirable alloy for forming the collapsible medical devicesof the present disclosure.

The metal wires used to fabricate the collapsible medical devices of thepresent disclosure may include wires having a diameter of from about0.002 to about 0.008 inches (about 0.051 to about 0.203 millimeters),including from about 0.002 to about 0.005 inches (about 0.051 to about0.127 millimeters). In some embodiments the wires have a diameter offrom about 0.003 to about 0.0035 inches (about 0.076 to about 0.089millimeters), and in some other embodiments, about 0.003 inches (about0.076 millimeters). In one specific embodiment, the wires have adiameter of about 0.006 inches (about 0.152 millimeters). The number ofwires in a wire mesh fabric (or tubular braid) may vary from about 36 toabout 144, desirably from about 72 to about 144, and in someembodiments, 144. The pick count of the wire mesh may vary from about 30to about 100, including from about 50 to about 80, including 70. Asnoted above, the wire diameter and the number of wires in the wire meshfabric will tend to influence the rigidity, strength, and flexibility ofthe resulting collapsible medical device. Numerous other embodiments andcombinations of wires sizes are contemplated within the scope of thisdisclosure.

In one specific embodiment of the present disclosure, a collapsiblemedical device including an open lumen from a proximal end to a distalend is formed from a braided tubular member by providingsecurement/attachment points (marker bands, for example as describedbelow) on both the proximal end and the distal end of the braidedtubular member. This embodiment is particularly useful when acollapsible medical device is desired that has attachment points on bothends of the device to allow for attachment to two separate additionalmedical devices. Additionally, this embodiment is particularly desirablewhen a collapsible medical device is desired that comprises only asingle layer of material.

In this particular forming process, the braided tubular member asdescribed above is first marked with braid markers (fabric ties, forexample) into the number of sections that will ultimately be combinedinto the securement/attachment points; that is, the braided tubularmember is sectioned-off as desired using braid markers to create thedesired number of securement/attachment points in the end device. Forexample, if it is desired to form a collapsible medical device includingan open lumen that has 12 securement/attachment points, then the braidedtubular member would be sectioned with 12 braid markers. Although thebraid markers may be introduced onto the tubular member in any suitablemanner, the braid markers are generally tied around each individualsection so as to form a tied bundle or tied section of wires. This tyingof the braid markers around each bundle or section of wires allows eachbraid marker to be easily removed later in the forming process asdescribed herein by simply untying each braid marker. In someembodiments of this forming method, the braided tubular member may beplaced on a mandrel or in a former or mold prior to the introduction ofthe braid markers so as to hold the braid stationary during the couplingprocess and to assist in the introduction of the braid markers onto thebraided tubular member. When more than one braid marker is used, thebraid markers are generally spaced evenly around the circumference ofthe braided tubular member, though this is not required in allembodiments. In one exemplary embodiment, when it is desired to producea collapsible medical device including four securement/attachment pointson the collapsible medical device, four braid markers are first evenlypositioned around the circumference of the braided tubular member inorder to create four distinct sections for further manipulation tocreate the desired open lumen from the proximal end to the distal end ofthe braided tubular member.

Turning now to the Figures, FIG. 1 illustrates a braided tubular memberincluding braid markers suitable for use in forming one embodiment of acollapsible medical device of the present disclosure. Braided tubularmember 2 has a proximal end 4, and a distal end 6, includes braidedwires 8, and braid markers 10, 11, 12, and 13. Braid markers 10, 11, 12,and 13 are generally evenly spaced about the circumference of braidedtubular member 2 such that in subsequent processing steps as describedherein, four generally equal sections of braided wires 8 are created.Distal wire ends 9 and proximal wire ends 15 are also shown in FIG. 1.

Once braid markers 10, 11, 12, and 13 have been introduced onto braidedtubular member 2 as illustrated in FIG. 1 and described above, braidedwires 8 are picked-out or unraveled from the distal wire ends 9 ondistal end 6 of braided tubular member 2 toward braid markers 10, 11,12, and 13 in a generally straight longitudinal line. Referring now toFIG. 2, there is shown braided tubular member 2 including braid markers10, 11, 12, and 13 wherein braided wires 8 on distal end 6 have beenunraveled along longitudinal lines L1 and L2 (toward proximal end 4) tocreate unraveled wire ends 9 such that the circled portion A remains ina substantially braided pattern. This unraveling in a generally straightline to each braid marker 10, 11, 12, and 13 from distal end 6 ofbraided tubular member 2 allows the braided pattern of braided wires 8between braid markers 10, 11, 12, and 13 to be substantially maintained;that is, the braided pattern of braided wires 8 between braid markers10, 11, 12 and 13 is not unraveled and remains substantially intact.

After the desired unraveling of braided wires 8 to braid markers 10, 11,12, and 13 has been completed as described above, wire ends 9 betweeneach of braid markers 10, 11, 12, and 13 are separated and collectedinto separate and distinct bundles. For example, when four braid markershave been utilized as described above, the wire ends on the braidedtubular member will be collected into four separate bundles of wireends. (If six braid markers are used, the wire ends would be collectedin six separate and distinct bundles, etc.) In other words, the quantityof braid markers may match the quantity of bundles. Each of the bundlesof wire ends then has a marker band (or other similarattachment/securement device) introduced thereon to hold and secure thewire ends in place and provide an attachment point.

Turning now to FIG. 3, there is shown braided tubular member 2 in acollapsed (or elongated) conformation having proximal end 4, distal end6, braid markers 10, 11, 12, and 13, wire ends 9, and including wirebundles 14, 16, 18, and 20. Each of wire bundles 14, 16, 18, and 20include a marker band 22, 24, 26, and 28, respectively. Before markerbands 22, 24, 26, and 28 are permanently attached to wire bundles 14,16, 18, and 20 as described below (by welding, soldering, adhesive, orthe like), braided tubular member 2 may be optionally collapsed (orelongated) so that all of the wire ends are substantially the samelength. By collapsing braided tubular member 2 during manufacturing, theresulting medical device including the open lumen will collapse to asmaller profile upon its use. When the smallest possible profile is notrequired for the medical device having an open lumen (for example whenthe resulting medical device is to be coupled to another medical devicethat has a larger collapsed profile thus necessitating the need for alarger deliver device), elongation during manufacturing is not required,although it still may be useful in some embodiments. The collapsiblemedical devices of the present disclosure including an open lumen from aproximal end to a distal end thereof may be formed to include 1, 2, 3,4, 5, 6, 7, 8, 9, 10, 11, 12, or more securement/attachment points asdisclosed herein. The securement/attachment points may be located onboth ends of the collapsible medical device (See FIGS. 4 and 5) or onlyon a single end of the collapsible medical device (See FIGS. 7 and 8),and allow the collapsible medical device to be attached to one or moreother medical devices or delivery devices.

After marker bands 22, 24, 26, and 28 have been positioned on wirebundles 14, 16, 18, and 20 respectively, marker bands 22, 24, 26, and 28are slid down wire bundles 14, 16, 18, and 20 placed at least a minimumdistance away from their respective braid markers in order to allow theformation the complete through lumen. This proper placement at somedistance from the respective braid markers allows the braid the abilityto expand properly as the desired wire length between braid markers ismaintained. In many embodiments, the desired minimum distance forplacement may be affected by the braid diameter, the forming diameter,and the number of connections desired. Generally, it is desirable thatthe wires from the braid marker to the marker band closely follow theirhelical pattern and be long enough to accommodate the formed diameter,which allows it to fit over a desired mandrel for forming.

After marker bands 22, 24, 26, and 28 are placed in the desiredposition, they are welded (or otherwise attached by solder, adhesive,etc.) to wire bundles 14, 16, 18, and 20 and any excess wire strands aretrimmed as desired using laser trimming or a suitable alternativeprocess.

Once marker bands 22, 24, 26, and 28 have been attached to wire bundles14, 16, 18, and 20 on distal end 6 of braided tubular member 2, asimilar process as described above is utilized on proximal end 4 ofbraided tubular member 2 to form wire bundles including marker bandsthereon and maintain the desired open lumen from proximal end 4 todistal end 6.

Referring now to FIG. 4, there is shown braided tubular member 2 incollapsed (elongated) conformation having proximal end 4 and distal end6. Distal end 6 includes wire bundles 14, 16, 18, and 20 having markerbands 22, 24, 26, and 28 thereon, respectively. Braid markers 10, 11,12, and 13 are also shown. Proximal end 4 further includes wire bundles30, 32, 34, and 36 having marker bands 38, 40, 42, and 44 thereon. Alsoshown on proximal end 4 are braid markers 46, 47, 48, and 49. An openlumen (not shown in FIG. 4) extends from proximal end 4 to distal end 6.

After marker bands 22, 24, 26, and 28 are secured to wire bundles 14,16, 18, and 20 on distal end 6 of braided tubular member 2 and markerbands 38, 40, 42, and 44 are secured to wire bundles 30, 32, 34, and 36on proximal end 4 of braided tubular member 2 as described above and theopen lumen extending from proximal end 4 to distal end 6 maintained, allof the braid markers 10, 11, 12, 13, 46, 47, 48, and 49 may be removedfrom braided tubular member 2 by untying each of braid markers 10, 11,12, 13, 46, 47, 48, and 49. Although is some embodiments it may bedesirable to remove the braid markers, such removal is not required inall embodiments. Because the wire lengths are set, braided tubularmember 2 may then be formed and heat treated into a suitable desiredshape using heat-treating processes and methodologies known on the artfor medical devices and memory-shape alloys.

Turning now to FIG. 5, there is illustrated braided tubular member 2 ofFIG. 4 after it has been heat-treated into a desired pre-setconfiguration to form heat set collapsible medical device 50. Heat setcollapsible medical device 50 includes center portion 37, proximal end 5and distal end 7. Proximal end 5 and distal end 7 of heat setcollapsible medical device 50 generally correspond respectively withproximal end 4 and distal end 6 of braided tubular member 2 of FIG. 4.Proximal end 5 of heat set collapsible medical device 50 includes markerbands 38, 40, 42, and 44 securing wire bundles 30, 32, 34, and 36,respectively. Distal end 7 of heat set collapsible medical device 50includes marker bands 22, 24, 26, and 28 securing wire bundles 14, 16,18, and 20, respectively. Heat set collapsible medical device 50includes an open lumen extending from proximal end 5 to distal end 7.

FIGS. 6A and 6B are flow diagrams of a method 100 for forming acollapsible medical device (such as medical device 50 shown in FIG. 5)having an open lumen from a proximal end to a distal end, according toone embodiment. Method 100 includes coupling 102 distal braid markers(such as braid markers 10, 11, 12, and 13), near a distal end of abraided tubular member (such as braided tubular member 2) comprising aplurality of braided wires (such as braided wires 8), and unraveling 104the braided tubular member along a longitudinal line extending from thedistal braid markers to the distal end of the braided tubular member toform distal bundles of unraveled wires (such as wire bundle 14, 16, 18,and 20). Method 100 further includes coupling 106 a securement mechanism(such as marker bands 22, 24, 26, and 28) to each bundle of unraveledwires. Method 100 further includes optionally elongating 108 thecollapsible medical device to a collapsed configuration and securing 110each securement mechanism to the respective bundle of unraveled wires.Method 100 further includes optionally coupling 112 proximal braidmarkers to a proximal end of the braided tubular member and unraveling114 the braided tubular member along a longitudinal line extending fromthe proximal braid markers to the proximal end of the braided tubularmember to form proximal bundles of unraveled wires. Method 100 furtherincludes coupling 116 a securement mechanism to each proximal bundle ofunraveled wires. Method 100 further includes elongating 118 thecollapsible medical device to a collapsed configuration and securing 120each securement mechanism to the respective proximal bundle of unraveledwires on the proximal end. Finally, method 100 includes heat treating122 the braided tubular member to form the collapsible medical device.

In an alternative forming process of the present disclosure, acollapsible medical device having an open lumen from a proximal end to adistal end in accordance with the disclosure herein may be formed usinga braided tubular member as described above having a proximal wire endand a distal wire end. In this alternative process, however, theproximal wire end is first inverted over itself toward the distal wireend. The inversion of the proximal end results in the formation of aninner layer and an outer layer (two separate layers) of the braidedtubular member. The open lumen is maintained from the proximal end tothe distal end of the inverted structure after the inversion.Additionally, with this alternative process, securement/attachmentpoints are present on only one end of the resulting collapsible device.Collapsible medical devices formed using this alternative process mayrequire a reduced number of steps in the collection and termination ofthe braid sections, thus making manufacturing easier and more costeffective.

Additionally, the inversion of the proximal end over itself as describedherein creates a clean, well-defined end that is desirable for deployinga graft or other medical device that requires precise placement accuracywithout having the braid attachment sections extend beyond the length ofthe device. Moreover, the inverted end may have higher radial force ascompared to the rest of the device due to the geometry of the invertedwires, which may be desirable in some embodiments where migrationresistance is desirable. Further, the two layers created by theinversion of the proximal end can readily accept and house a third,potentially more occlusive layer, therebetween to improve the resultingproperties of the finished device. In some embodiments, a third metalliclayer, such as a braided nitinol layer of the like, for example, may beintroduced between the inner and outer layer formed by the inversion ofthe proximal end. In other embodiments, a third fabric layer, such as abraided polyester fabric layer or the like, for example, may beintroduced between the inner and outer layer formed by the inversion ofthe proximal end. In some embodiments, the two layers created by theinversion can house two, three, four or more additional layers therein.

After the inversion of the proximal end and the forming of the inner andouter layers, the proximal wire end and the distal wire end are alignedgenerally or substantially longitudinally for further manufacturing.Once the longitudinal alignment of the proximal wire end the distal wireend is complete, the process proceeds generally as disclosed above toform the final device. In particular, one or more braid markers areattached (depending upon how many securement/attachment points aredesired, as described above) to both the inner layer and the outer layerto allow further processing of both layers. In some embodiments, theinverted braided tubular member may be placed on a mandrel, or in aformer or mold, prior to the introduction of the braid markers so as tohold the braid stationary during the coupling process. Additionally, insome embodiments as noted above, the inner layer and the outer layer mayhouse therebetween one or more additional layers, such as anothermetallic layer (nitinol or the like) to increase the occlusiveproperties of the resulting medical device. When present, this third,in-between metallic layer, will have been introduced between the twolayers formed by the inversion and subsequently longitudinally alignedwith these two layers and will also have braid markers attached theretosuch that all three layers are brought together and coupled by the braidmarkers and prepared for further manufacturing as described herein.After the braid markers are attached to both the inner layer and theouter layer (and optionally the third in-between metallic layer as notedabove), both layers are simultaneously unraveled along a generallylongitudinal line that extends from each braid marker to the proximalend wire and the distal end wire (which are longitudinally aligned asnoted above) to form one or more sections of unraveled wires betweeneach braid marker (or one set of unraveled wires if a single braidmarker is utilized).

Once the unraveling is complete and the formed sections gathered, asecurement/attachment mechanism, such as a marker band, is coupled toeach section of unraveled wires. After the securement mechanism(s) hasbeen coupled to the unraveled wire section(s), the braided tubularmember may be optionally elongated as described above, and eachsecurement mechanism is secured to each section of unraveled wires afterproper positioning. In this embodiment, because the proximal end of thestarting braided tubular member is inverted over itself andlongitudinally aligned with the distal end after inversion, only one setof securement/attachment mechanisms is needed to form the collapsiblemedical device; that is, in this forming process only one end of thestructure will include securement/attachment mechanisms. As with theprevious embodiments described above, once the securement mechanismshave been secured to the sections of unraveled wires, the resultingstructure may be heat treated into a desired heat set configuration,which includes an open lumen from a proximal end to a distal end.

In some embodiments of the present disclosure, it may be desirable toprovide a medical device that has substantial occlusive properties; thatis, occlusive properties that may be generally challenging to obtainusing solely braided metallic layers. To form such a device havingincreased occlusive properties in accordance with the presentdisclosure, a third (or more) occlusive fabric layer, such as a braidedpolyester fabric layer, may be introduced between the inner and outerlayers formed by the inversion as described above. In this embodimentwhen a braided fabric layer is desirable, braid markers are first placedon both the inner and outer layers (the two layers formed by theinversion) as described above, and these two layers unraveled togethertoward the braid markers as set forth herein. Separate marker bands arethen placed on the inner layer and the outer layers such that the markerbands line up generally on top of each other but the layers continue tobe separated. After this, the inner and outer layers are heat treated toset the desired final shape (this is done prior to the introduction ofthe braided fabric layer due to the melting point of the fabric beinglower than the heat set temperatures). After heat treatment to set theshape is complete, the braided fabric layer (or the like) is placed inbetween the inner layer and the outer layer and marker bands are placedon the inner and outer layer together to form the device including threeseparate layers. The braided fabric layer (or the like) may then besutured or otherwise attached in one or more locations to the inner andouter layer to restrict its movement and hold it in the desiredlocation. The marker bands initially placed on the inner and outerlayers are then removed such that the remaining marker bands secure thelayers and provide a device with increased occlusive properties. In someembodiments, it may be desirable for the braided fabric layer to bepositioned within the inner and outer layers such that is it at or nearthe end of rolled over end to increase the occlusive properties of theresulting device.

Turning now to FIG. 7, there is illustrated a collapsible medical deviceincluding an open lumen from a distal end to a proximal end formed inaccordance with the alternative forming embodiment described aboveincluding the initial inversion of a braided tubular member over itselfto form a dual layer structure. FIG. 7 shows collapsible medical device52 including proximal end 54 and distal end 56. An open lumen 58 extendsbetween proximal end 54 and distal end 56 to allow fluids to passtherethrough without obstruction. Collapsible medical device 52 alsoincludes outer layer 60, inner layer 62, and middle fabric layer 53located between outer layer 60 and inner layer 62 (as shown in FIG. 7with outer layer 60 partially cut away to reveal middle fabric layer53). As illustrated in FIG. 7, collapsible medical device 52 includes asingle marker band 64 on distal end 56 securing wires 66 in place whilemaintaining open lumen 58.

Referring now to FIG. 8, there is shown another collapsible medicaldevice including an open lumen from a distal end to a proximal endformed in accordance with the alternative embodiment described aboveincluding the inversion of a braided tubular member over itself to forma dual layer structure. FIG. 8 shows collapsible medical device 68including open lumen 70. Collapsible medical device 68 further includesinner layer 72 and outer layer 74. As illustrated in FIG. 8, collapsiblemedical device 68 includes marker bands 76, 78, 80, 82, 84, 86, 88, 90,92, 94, 96, and 98. Thus, collapsible medical device 68 provides 12points of attachment.

FIG. 9 is a flow diagram of a method 200 for forming a collapsiblemedical device (shown in FIG. 8) having an open lumen extending from aproximal end to a distal end. Method 200 includes inverting 202 aproximal wire end over itself toward a distal wire end of a braidedtubular member to form an inner layer and an outer layer (two separatelayers, but connected or continuously formed from a single braidedtubular member) of the braided tubular member. Method 200 furtherincludes aligning 204 the proximal wire end and the distal wire endlongitudinally and attaching 206 one or more braid markers (dependingupon how many securement points are desired, as described above) to boththe inner layer and the outer layer. Method 200 further includesunraveling 208 the inner layer and the outer layer along a longitudinalline that extends from each braid marker to the proximal end wire andthe distal end wire to form one or more sections of unraveled wiresbetween each braid marker (or one set of unraveled wires if a singlebraid marker is utilized), gathering 210 the formed sections, andcoupling 212 a securement mechanism to each section of unraveled wires.Method 200 further includes elongating 214 the braided tubular memberand securing 216 each securement mechanism to each section of unraveledwires. Finally, method 200 includes heat treating 218 the braidedtubular member to form the collapsible medical device including an openlumen.

The collapsible medical devices of the present disclosure including anopen lumen extending from a distal end to a proximal end may be used asstandalone medical devices or may be used in combination with anothermedical device or multiple other medical devices. When used as astandalone medical device, the attachment point or points present on thedevice may be attached directly to a delivery device. When used incombination with another medical device, the attachment points presenton the device may be attached directly to the other medical device. Byhaving an open lumen from a proximal end to a distal end as describedherein, the collapsible medical devices of the present disclosure allowfluids and/or materials to pass therethough without significantobstruction.

Referring now to FIGS. 10 (side view) and 11 (top view), there is showna collapsible medical device of the present disclosure formed to include12 securement points used in combination with a secondary medical device(a mitral valve) that includes 12 attachment points for mating with the12 securement points on the collapsible medical device to allow thedevices to be securely coupled to one another for use. Such coupling asdescribed herein allows both devices to assume the same conformation(collapsed or expanded) as desired during introduction and use in thebody. As illustrated in FIGS. 10 and 11, collapsible medical device 300includes wires 302 forming braided tubular member 303, which is attachedto mitral valve 304. Mitral valve 304 extends through collapsiblemedical device 300 through open lumen 306 such that mitral valve 304 maybe introduced into the body at the desired location without interferencefrom collapsible medical device 300.

Collapsible medical device 300 is coupled to mitral valve 304 atattachment points 308, 310, 312, 314, 316, 318, 320, 322, 324, 326, 328,and 330. Although illustrated in FIGS. 10 and 11 as a crimp weld,collapsible medical device 300 may be attached to mitral valve 304 inmany different ways including, for example, by adhesive, by welding, bysoldering, by suture, by fabric, and the like. Further, althoughillustrated in FIGS. 10 and 11 as including 12 attachment points and 12securement points, collapsible medical device 300 and mitral valve 304,respectively, may include any number attachment and securement pointsthat enables collapsible medical device 300 and mitral valve 304 to becoupled to one another.

In the embodiment illustrated in FIGS. 10 and 11, collapsible medicaldevice 300 is sized and configured to seal against the left atrium whenused in combination with mitral valve 304, although other configurationsand uses are within the scope of the present disclosure. Thisconfiguration allows fluid to easily pass through mitral valve 304during use while still allowing collapsible medical device 300 toperform its intended sealing function.

Although a number embodiments of this disclosure have been describedabove with a certain degree of particularity, those skilled in the artcould make numerous alterations to the disclosed embodiments withoutdeparting from the spirit or scope of the disclosure. All directionalreferences (e.g., upper, lower, upward, downward, left, right, leftward,rightward, top, bottom, above, below, vertical, horizontal, clockwise,and counterclockwise) are only used for identification purposes to aidthe reader's understanding of the present disclosure, and do not createlimitations, particularly as to the position, orientation, or use of thedisclosure. Joinder references (e.g., attached, coupled, connected, andthe like) are to be construed broadly and may include intermediatemembers between a connection of elements and relative movement betweenelements. As such, joinder references do not necessarily infer that twoelements are directly connected and in fixed relation to each other. Itis intended that all matter contained in the above description or shownin the accompanying drawings shall be interpreted as illustrative onlyand not limiting. Changes in detail or structure may be made withoutdeparting from the spirit of the disclosure as defined in the appendedclaims.

Any patent, publication, or other disclosure material, in whole or inpart, that is said to be incorporated by reference herein isincorporated herein only to the extent that the incorporated materialsdoes not conflict with existing definitions, statements, or otherdisclosure material set forth in this disclosure. As such, and to theextent necessary, the disclosure as explicitly set forth hereinsupersedes any conflicting material incorporated herein by reference.Any material, or portion thereof, that is said to be incorporated byreference herein, but which conflicts with existing definitions,statements, or other disclosure material set forth herein will only beincorporated to the extent that no conflict arises between thatincorporated material and the existing disclosure material.

What is claimed is:
 1. A collapsible medical device comprising: atubular member formed of a plurality of wires and having a preset,expanded configuration and a collapsed configuration, the tubular memberhaving a center portion wherein the wires are in a braidedconfiguration, and a distal end and a proximal end wherein the wires arein an unraveled configuration; an open lumen extending from the proximalend to the distal end configured to allow passage of a fluidtherethrough in the preset, expanded configuration; at least one braidmarker coupled to the tubular member at an interface between the centerportion and the proximal end; at least one braid marker coupled to thetubular member at an interface between the center portion and the distalend; at least one securement mechanism coupled to the proximal end; atleast one securement mechanism coupled to the distal end; wherein eachsecurement mechanism is configured to secure at least a portion of theplurality of wires in the unraveled configuration near an outercircumference of the open lumen; and wherein the plurality of wires inthe unraveled configuration are unraveled along a longitudinal linebetween the respective at least one securement mechanism coupled to theproximal and distal ends and the respective at least one braid marker atthe interfaces between the center portion and the proximal and distalends.
 2. The collapsible medical device of claim 1, wherein the at leastone securement mechanism coupled to the proximal and distal ends is amarker band.
 3. The collapsible medical device of claim 1, wherein theplurality of wires are constructed of a memory-shape alloy.
 4. Thecollapsible medical device of claim 3, wherein the memory-shape alloy isnitinol.
 5. The collapsible medical device of claim 1, wherein theplurality of wires are substantially the same length.
 6. The collapsiblemedical device of claim 1, wherein the device includes from 1 to about12 securement mechanisms on each of the proximal end and the distal end.